Description of the Related Art
Early diagnosis of potentially cancerous tissue is an important step in the treatment of cancer because, the sooner that cancerous tissue can be treated, and the better the patient's chances are for survival. Typical diagnostic procedures involve biopsying tissue at a site of interest. In the case of lungs, lung cancer can be difficult to diagnose due to the difficulties in accessing airways near areas of interest. Areas of interest may present as lung nodules—small tissue masses in the lung that may range in size between 0.5-30 mm—that typically are biopsied to ascertain whether the tissue therein is cancerous or otherwise diseased. In some instances treatment of tissue in an area of interest can include delivery of chemicals (e.g., ablative chemicals) or other substances.
Existing systems typically are constrained by difficulties in accessing lung nodules, especially in the smaller peripheral airways that may be too narrow to accommodate larger catheters and biopsy/substance delivery apparatuses. Further, the biopsy/substance delivery needles normally are straight and relatively inflexible. Thus, the biopsy/substance delivery needles can limit the articulation of a bronchoscope or can be difficult to pass through a working channel of a bronchoscope when the bronchoscope is articulated around a tight corner. In some instances, the material of the needle may inelastically yield, which can result in a bent needle that is difficult to control. In addition, the straight biopsy needles obtain samples along an axis of the needle through back and forth cycling of the needle. Thus, obtaining multiple samples from different regions of a single nodule, for example, can be difficult and can require repeated repositioning of the bronchoscope or guide sheath, for example. Furthermore, delivery of substances to different regions of a single nodule can be difficult.